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In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
悪性メラノーマにおけるアポトーシスエフェクタ Apaf-1 の無活性化
M S Soengas1, P Capodieci, D Polsky
1Cold Spring Harbor Laboratory, New York 11724, USA.
Nature
|February 24, 2001
まとめ
転移性メラノーマは,プログラム細胞死のための重要なタンパク質であるApaf-1をしばしば無効化する. Apaf-1レベルを回復させることで,化学抵抗性メラノーマ細胞を治療に再敏感化することができます.
科学分野:
- 腫瘍学 腫瘍学
- 分子生物学は分子生物学である.
- がん研究 がん研究
背景:
- 転移性メラノーマは,分子理解が乏しい化学抵抗性がんである.
- p53変異は,化学抵抗性がんでは一般的ですが,メラノーマでは稀です.
- Apaf-1は細胞死のエフェクタであり,p53に依存したアポトーシスを媒介する.
研究 の 目的:
- 転移性メラノーマにおけるApaf-1の役割を調査する.
- メラノーマの化学抵抗を支える分子機構を理解する.
主な方法:
- 転移性メラノーマにおけるApaf-1発現の分析.
- Apaf-1 アレル喪失と甲基化の調査.
- メラノーマの細胞系を5-アザ-2'-デオキシチチジン (5aza2dC) で治療する.
- Apaf-1レベルを回復するために遺伝子転送.
主要な成果:
- 転移性メラノーマは,しばしばアパフ-1の発現を失い,アレル喪失と関連しています.
- Apaf-1の損失は,メチル化阻害 (5aza2dC) によって逆転することができます.
- Apaf-1-ネガティブなメラノーマは,化学抵抗性および欠陥アポトーシスを表しています.
- Apaf-1を復元すると,化学反応感受性を高め,アポプトシス欠陥を回復します.
結論:
- Apaf-1の無活性化は,転移性メラノーマの発症における重要な出来事です.
- Apaf-1の喪失は,メラノーマにおける化学抵抗と欠陥アポトーシスに寄与する.
- Apaf-1の不活性化により,メラノーマにおけるp53変異の頻度が低いことが説明できる.
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